Upper Arkansas River. FISH SURVEY AND MANAGEMENT DATA Greg A. Policky - Aquatic Biologist (Salida)

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1 FISH SURVEY AND MANAGEMENT DATA (Salida) / General Information: The upper Arkansas River offers excellent fishing for brown and rainbow trout from Leadville through Canon City. Anglers enjoy plentiful access (68% of this reach is open to the public) and with up to 5 trout per mile anglers catch rates are high for both walk/wade and float anglers. Lake Fork Creek to Parkdale designated Gold Medal January 214. Location: Lake, Chaffee, and Fremont Counties. See page 2 for map. For further information go to or Recreational Management: Wildlife ( ), AHRA ( ). Fishery Management: Coldwater angling for brown and rainbow trout. Amenities and General Info. Regulations Sportfishing Notes Over 8 miles of public access for walk/wade anglers (detailed maps available from several private sources) Numerous boat access points, facilities, and amenities managed by AHRA (see link above) Guided wade or float fishing available (see AHRA Fishing Outfitters List from above link) Previous Stocking The Arkansas River is predominantly a wild brown trout fishery, however rainbow trout have been historically stocked to increase species diversity and angling opportunity. A whirling disease resistant rainbow strain has been stocked since 29 in an attempt to establish a self-sustained rainbow trout population. Statewide bag and possession limits apply for most of river except as follows From US Hwy 24 overpass below Leadville downstream to near Two Bit Gulch (5.8 miles) Artificial flies and lures only Bag and possession limit for trout one fish 12 or shorter From Stockyard Bridge (Chaffee Co Rd 12) below Salida downstream to Badger Creek (7.5 miles) Artificial flies and lures only All rainbow trout must be returned to the water immediately Limit on brown trout is four fish of any size Brown Trout Most common species representing over 75% of the trout community Average 12 with high numbers to 16 and an occasional fish taken over 2 Rainbow Trout Add angling diversity to the trout community Average 14 but grow well in the Arkansas with a higher proportion reaching lengths over 16 and 2 Popular Insect Hatches BWO (mid-march to mid- May) Mother s Day caddis (mid- April to mid-may) Stoneflies, mayflies, hoppers (summer through fall) Midges (all winter)

2 MAP AND ACCESS INFORMATION

3 NUMBER >=14"/acre BIOMASS (lbs/acre) Number Upper Arkansas River 215 RIVER SURVEY DATA ARKANSAS RIVER TROUT DISTRIBUTION AT WELLSVILLE, Length Conversions: 25 mm = 1 inches 3 mm = 12 inches 35 mm = 14 inches 4 mm = 16 inches Rainbow (Wild) Brown Length (mm) ARKANSAS RIVER TROUT BIOMASS, Gold Medal Standard - 6 lbs/acre YEAR Wellsville Big Bend Coaldale Hayden Ranch (AR6a) ARKANSAS RIVER TROUT >=14"/acre, Gold Medal Standard - 12 >=14"/acre YEAR Wellsville Big Bend Coaldale Hayden Ranch (AR6a)

4 216 FISHING FORECAST Angler use reached a significant milestone in 212 with 1563 anglers fishing the river throughout the year between Leadville and Parkdale. This is up from just under 7 annual anglers in 1995 and 27. The Arkansas River ranks as the favorite fishing destination in Colorado according to 28 and 212 Angler Survey conducted by the University of Wisconsin Stevens Point. One-hundred and two miles of the Arkansas River from Lake Fork Creek to Parkdale was designated as Gold Medal water in January 214, signifying it as one of the finest fisheries in the state. Trout catch rates, size, and vigor should be good in 216 and with abundant public access anglers can find ample opportunity to enjoy this excellent freestone fishery. Trout number and size has declined river-wide the last several years, averaging over 2 trout/mile with fewer fish over 14 inches. Brown trout are the most prevalent species found and are caught most often by anglers. They average 12 inches long with good numbers to 16 inches and an occasional fish taken over 2 inches. They sustain themselves through natural reproduction. Rainbow trout density and biomass has also declined the last several years. Rainbow trout grow well in the Arkansas, averaging 14 inches, with a higher proportion reaching lengths over 16 and 2 inches. Historically, rainbow trout fry were eliminated by mining pollution and whirling disease (WD). Heavy metals no longer kill fry and six inch WD resistant rainbow trout (Hofer/Colorado River) have been stocked since 29 in hopes of establishing a self-sustained rainbow trout population. Wild fry were produced in 212 but very few have been collected since. This stocked hybrid has recruited poorly to age 1, perhaps struggling to survive in the Arkansas River. Wild, more genetically fit strains will likely be considered in the future. There is year round insect action on the Arkansas River for the fly fishing enthusiast! The most famous hatch on the Arkansas River is the Mother s Day caddis fly hatch. It begins in mid-april near Canon City and progresses upriver as water temperatures warm to about 54 F. Stoneflies and mayflies hatch throughout the summer and fall along with good hopper action. Midges are the winter mainstay and from mid-march to mid-may baetis mayflies are abundant, arguably rivaling the caddis hatch in fishing popularity. Regardless of season, a two fly setup is recommended such as a dry/dropper combination. You can imitate two insect life stages or different species with this setup and cover more water. The top fly often acts as an attractor or strike indicator for the trailer fly and double hookups can occur! Lure fishermen do very well with Panther Martins and small plugs that imitate fingerling trout and bait anglers find ample success with natural baits such as night crawlers. Bait angling is particularly effective during runoff when most fish are close to the bank where the current is less. Bait angling is allowed most places on the Arkansas River except for a five mile stretch in Hayden Flats below Leadville and a 7.5 mile stretch below Salida from Stockyard Bridge to Badger Creek. One last tip is worth mentioning. The more you know about the life history, habits, and habitat preferences of the species you re fishing for the more successful you can be. For example, as water temperature warms in early spring fish will move out of deeper, winter pool habitat into the head of 3-5 deep runs. Upstream riffles produce a lot of food that trout are keying into. The best runs have boulders scattered throughout them where fish can rest and hide outside of the current but where food drifts nearby.

5 MANAGEMENT IMPLICATIONS The Arkansas River trout population below Lake Creek has changed dramatically since 212. Trout fed efficiently, grew exceptionally well and were extremely fit in 212 due to low flows throughout the growing season. Trout density, biomass and number over 14 inches was astounding (136 trout >= 14 inches/acre at Coaldale). Unfortunately, the fishery suffered from additional water in 213 and 214. Trout biomass and the number of large fish declined to just above the minimum gold medal standards. Fry production was poor in 213 and 214 as well. Elevated spring flow delayed egg development and hatching/emergence, resulting in high fry mortality during runoff. Brown trout fry production responded favorably to moderated spring and fall flows in 215 as did fitness of larger fish, the best indicator of improving habitat. Hofer/Colorado River rainbow trout survival and recruitment to age-1 has been poor even though they were six inches long when stocked. Adult stock has become very low and rainbow trout composition at Wellsville has steadily declined since 212, currently comprising two percent of the trout community. Wild, more genetically fit strains will likely be considered in the future. The fishery will improve with proper flow management including egg hatching and fry emergence, trout feeding efficiency, insect hatches, and angler satisfaction. Water flow is the single most important habitat variable affecting fisheries in the Arkansas River, whether by itself or in combination with other factors. The Arkansas River trout population above Lake Creek is a product of the unique habitat found in this reach. This fish population has improved dramatically since heavy metal remediation and with favorable flow regimes most years, trout biometrics remain consistently high, remarkable for a river of this elevation. Instream and riparian habitat enhancement efforts completed in 214 should further improve this fishery. It has been suggested over the years to introduce a large forage item to the Arkansas River biota to boost trout growth and fitness. Pteronarcys californica, the giant salmonfly, was chosen to enhance forage opportunities for trout, to resurrect a native population that experienced a local extinction, and to enhance fishing opportunity. Approximately 133, nymphs were stocked at eight different locations (six in 212) of the Arkansas River in the southern part of Chaffee County and northern part of Fremont County. Nymphs begin molting in early May and numerous exoskeletons are observed at all river release sites by late May in 213 and 214. The hatch seemed to closely follow the true onset of runoff when water temperature reached 5 F. Despite considerable effort in 215, none were found. Hopefully they will be found in 216 and meanwhile, habitat based factors (e.g. water quality, sedimentation) will be assessed to try to explain their apparent decline and future viability in the Arkansas River.